In November 1971, a man known only by the alias Dan Cooper executed one of America's most daring unsolved crimes by extorting a $200,000 ransom for a hijacked Boeing 727. After receiving the cash and four parachutes during a refueling stop, he ordered the plane back into the air and then, somewhere over the rugged wilderness of the Pacific Northwest, lowered the aircraft's aft stairs and leapt into the stormy night. Despite one of the most extensive manhunts in U.S. history, no definitive trace of Cooper or his parachute was ever found. The only physical evidence to surface was a small, decaying bundle of the ransom bills, discovered by a boy on a riverbank nine years later, a clue that has only served to deepen the mystery surrounding the hijacker's identity and whether he survived the jump.